Now Topas has anisotropy built in the GUI version too. No script is needed. Peter .................................................................... Peter Y. Zavalij, PHD Director - X-ray Crystallographic Center University of Maryland, College Park, MD 20742
On Tue, Aug 2, 2022 at 9:16 AM Radovan Cerny <radovan.ce...@unige.ch> wrote: > Dear Enyuan, > > > as Wojciech said, you have certainly the effect of stacking faults. LiOH > is a tetragonal structure and the layers are parallel with ab plane. It > means that the faulting has an effect on the reflections with l-index > non-zero. The faulting can be roughly understood as a size effect in the > direction of c-axis. From your WH plot it is evident that the reflections > 110 and 200 are not-affected while all the others with l non-zero are > affected. With increasing l-index, the effect is stronger. > > You can easily refine this anisotropy with many Rietveld programs. Maybe > somebody can provide a script for Topas for example or in Profex or > Fullprof such models may be available. > > > It stays to explain why the cycling of a battery introduce stacking faults > in LiOH. > > > Best regards > > > Radovan > > > Radovan Cerny > Laboratoire de Cristallographie > Université de Genève > 24, quai Ernest-Ansermet > CH-1211 Geneva 4, Switzerland > Phone : [+[41] 22] 37 964 50, FAX : [+[41] 22] 37 961 08 > mailto : radovan.ce...@unige.ch > URL : http://www.unige.ch/sciences/crystal/cerny/rcerny.htm > > > ------------------------------ > *De :* rietveld_l-requ...@ill.fr <rietveld_l-requ...@ill.fr> de la part > de wslawin...@chem.uw.edu.pl <wslawin...@chem.uw.edu.pl> > *Envoyé :* mercredi, 20 juillet 2022 11:16 > *À :* rietveld_l-requ...@ill.fr > *Objet :* Re: understanding peak width broadening during LiOH growth > > > Dear Enyuan, > > LiOH is definitely a layered structure. In such kind of structures, it is > likely that extra anisotropic broadening can be caused by “stacking > faults”. In your case, peaks with mixed kh and l index are generally > broader than those 00l or hk0. > > It would require a detailed study but you can also look at my paper > > https://pubs.acs.org/doi/full/10.1021/acs.inorgchem.6b02247 > > With best regards, > > Wojciech Slawinski > > wslawin...@chem.uw.edu.pl > > > > *From:* rietveld_l-requ...@ill.fr <> *On Behalf Of *Enyuan Hu > *Sent:* Wednesday, July 20, 2022 5:41 AM > *To:* RIETVELD_L Distribution List <rietveld_l@ill.fr> > *Subject:* understanding peak width broadening during LiOH growth > > > > Hi all, > > > > I am seeking help on understanding why peak broadens during LiOH crystal > development. > > > > Background: we have identified LiOH as a major component in the interphase > of batteries and we are trying to understand how it evolves. We obtained > the Williamson-Hall plot for the LiOH phase as shown below. Black: 1st cycle; > Red: 5th cycle; Green: 30th cycle. So the green one has obvious anisotropic > broadening and we found literature that suggests this is due to > pallet-shaped LiOH. But going from 1st cycle to 30th cycle (black to > green), the peak width is in general more broadened. We thought LiOH would > grow in size so the peaks should become more sharp. So this is sort of > against our expectations. Can such a phenomenon be explained by strain and > if so, can anyone provide comments or suggestions? Thank you! > > > > Regards > > Enyuan > > > > [image: image.png] > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > Please do NOT attach files to the whole list <alan.he...@neutronoptics.com > > > Send commands to <lists...@ill.fr> eg: HELP as the subject with no body > text > The Rietveld_L list archive is on > http://www.mail-archive.com/rietveld_l@ill.fr/ > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > >
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com> Send commands to <lists...@ill.fr> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
